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#221
09-28-2009, 07:02 AM
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No arguements/opinions of caliber or bullet weight/type here for me.
My feeling was always "there's no such things as too much". When I carried a revolver (.357 or .44) I carried 4 speed loaders in the belt pouches and a spare box on the car seat. The speed six back up gun in my winter jacket right hand pocket had a speed loader in the left hand pocket. When I carried my .45 ACP I had 4 magazines in pouches on my belt and a box of ammo on the seat of the car. Better to have it and not need it than need it and not have it. PS. Most of the guys I worked with laughed at me for carrying that much ammo. I never needed it. Good thing, too. 
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#222
09-28-2009, 08:17 AM
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Quote:
I have had his book, "Hell, I was There" since 1981 IIRC? and have read it several times. Time to read it again actually. I lent it once to a RMC friend who loved shooting game in the UK, - mainly pheasent 'on the wing' ( flying,) in my friend's case. I thought he might find it just a touch "too American", but he loved the book! Regards, Anthony.
__________________
If you have to fight, do not fear death. We will all die one day, so fight skillfully and bravely! And if it is to be that you die, then at least go to God proudly. Meet him as the proud warrior that you once were, and not as a sniveling coward. Nobody lives forever.
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#223
09-28-2009, 07:04 PM
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Quote:
__________________
"Anyone too proud to learn is too arrogant to win a fight." Gabe Suarez (A pot stirrer looking for a better way)
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#224
09-28-2009, 07:49 PM
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Quote:
__________________
Matt John 14:6 “Your enemy is he who will give his life to kill you,” ………. “Your enemies are they that wish you and your children and your grandchildren dead and who are willing to sacrifice themselves, or support those fanatics who will sacrifice themselves, to see you and your institutions destroyed. You haven’t figured that out yet – the majority of you fat, sleeping, smug, infinitely stupid Americans and Europeans.” – Dan Simmons, 2006
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#225
09-29-2009, 08:30 AM
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I am comfortable with my Glock 30, my Glock 22, or my S&W M&P 9. I carry an extra mag with each one. Unless I knew in advance what kind of situation I would face, I could not make a case for anyone of them over the other.
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#226
10-01-2009, 10:35 AM
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Quote:
The fallacy of your belief is so contrary to common experience that it is amazing that it remains in existence. Most of us have shot the same cartridges from different guns and we all know that a lighter gun tends to hurt more or feel more uncomfortable to an extent depending on your skill, hand toughness and machismo. Given enough bullet momentum we can always reach a point where anyone will feel this difference. There is no way in which the difference can be doubted but most of us know that momentum is conserved and so, since the forward momentum of the bullet and ejecta are the same then the rearward momentum of the light gun is the same as the rearward momentum of the heavy gun. To have the same momentum the light gun has to be traveling faster and therefore it has more energy. It is the extra energy, or the extra velocity (which is much the same thing) that causes the extra discomfort. It is possible to show this with basic calculus but consider a simple case where one gun is half the weight of the other. Let us say x and 2x. Let us say the velocity of the heavy gun is y. Then the velocity of the light gun must be 2y. So the momentum of the light gun is x*2y and that of the heavy gun 2x*y and, since both equal 2xy, they have equal momentum, which is what we wanted. But kinetic energy equals mvv/2, so the KE of the light gun is: x*2y*2y/2 = 2xyy The KE of the heavy gun is: 2x*y*y/2 = xyy In other words the recoil KE of the light gun, the one that hurts more, is twice the energy of the heavy gun but the recoil momentum is the same. Elmer Keith's small bore ultra high velocity bullet is just an extension of this fundamental misunderstanding. It is not the energy of the bullet that mattered but how much of that energy was transmitted to the rabbit. The bullet went right through and took almost all its energy with it. As we have seen in another thread, many bullet wounds produce no pain at the time. The rabbit would have felt an odd but not painful sensation as a small amount of the bullets momentum was transferred but it would be a sensation outside its direct experience or the range of stimuli to which rabbits have an instinctive response and of no more significance in the rabbit’s brain than a gust of wind. "Hmm! Wonder what that was? Can't waste time on it! Back to work!" continued below Last edited by English : 10-01-2009 at 10:41 AM.
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#227
10-01-2009, 10:36 AM
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Continued from above
Energy is defined in physics as the capacity to do work and the work that a bullet does on tissue is disrupting structural bonds. In the immediate vicinity of the bullet track, cell walls are split and the tissue is turned to mush. That mush is accelerated to the side to make room for the bullet and, in turn, pushes the next "cylinder" round the bullet track out, which pushes the next one out and so on. It is easy to see that each successive cylinder is accelerated more slowly as it has a greater circumference. The faster the bullet, the faster the mush must be moved out of the way and the greater will be the outward acceleration of surrounding tissue and the size of the temporary cavity. If you think of each of these cylinders surrounding the bullet track as having some small thickness, say a quarter of an inch, then as a cylinder moves out to some greater diameter its circumference is stretched and so its thickness must be reduced. The tissue is stretched in one direction and compressed in another. That is, it is stretched circumferentially and compressed radially. It is the height of ignorance, even for medics, to say, as the IWBA did, that tissue is elastic and therefore this simultaneous stretching and compression is unimportant as a wounding mechanism. Much connective tissue is highly inelastic. It needs to be or we would waste much of the energy and more of the precision of our movements as our tendons stretched and sprung back. Our cell walls are made of collagen, the same material as connective tissue and have limited elasticity. Complex collagen structures in combination with elastin provide graded elasticity for different functions in the body but all of it has very limited elasticity. The structure of voluntary muscle is essentially layers of contractile cells attached at angles between sheets of connective tissue. Alternate sheets are pulled in opposite directions with one side of each pair connecting to the ligament and the other connecting to the tendon. Like tendons, it is important that this material is not elastic and so traumas that tend to stretch it will tend to rip it and tear away the connections of the contractile cells. Then that part of the muscle will stop functioning. The cells might receive nerve impulses that make them contract but they will pull against nothing if they do so. Involuntary muscle such as that of the bladder can be stretched to many times its natural length. It is and amazing phenomenon but it works only when don slowly. Do it fast and it tears. Voluntary muscles are elastic in the direction of their action as long as they have enough time. To anyone who has torn a muscle in some accident that stretched muscle to quickly, the concept of limited muscular elasticity should be clear. Muscle cannot stretch at the speed and extent it needs to accommodate much of the temporary cavity. The result is tears in the tissue. Close in to the bullet track and outside the mush zone these are big tears. Further out they become smaller and smaller until they are micro tears. Even with micro tears, affected muscle cannot function. This is a wounding mechanism which physically degrades the fighting ability of the person shot by removing muscle function. It is a mechanism not considered by the IWBA. This tearing will also produce internal and external bleeding which, if it involves a large enough body volume, and if not treated, can produce death. Major blood vessels sufficiently close to the bullet track will also tend to be separated and will increase the rate of bleed. Bleed out was one of the major causes of death considered by the IWBA to be a valid "target" of bullet power and design. Unfortunately bleed out takes far too long to stop a fight before the BG can do major damage to others but never mind - the IWBA thought it was important. Floppy, non muscular organs like the liver are usually destroyed by high energy transfer bullet wounds because they have little resistance to tearing and, short of a liver transplant, will usually result in death but not, normally, quickly enough. Short of the CNS, the only major organ which will stop a fight quickly is the heart, but how quickly does it do so? According to the FBI, the answer is 15 to 30 seconds though some insist it is only 15 seconds. Within this time, as they say, a determined man can continue to function at a lethal level on the oxygen reserves in brain and muscles with his heart completely shot out. 15 seconds is surely enough time for 30 shots including a single reload. Follow the WT advice to keep shooting till the threat has ceased, and that is true whether you are shooting pistol, rifle or shotgun. By keeping shooting you progressively degrade the combat capability of your opponent and continue to disrupt his OODA loop as he tries to shoot you or someone else. continued below Last edited by English : 10-01-2009 at 10:42 AM.
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#228
10-01-2009, 10:37 AM
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continued from above
So what happens to a bullet's energy as it creates its wound and why do we continue to think that it is momentum produces penetration and damage? The instantaneous energy released by a bullet in tissue is proportional to the square of its speed and proportional to the product of its coefficient of drag and its frontal area. In other words, streamlined bullets, like Elmer Keith's discussed above, give up their energy slowly, Wide bullets give up their energy quickly, and very fast bullets give up their energy very very quickly at about a rate proportional to the square of their velocity. A bullet that stays in the body transmits all of its momentum to the body. Since part of the recoil momentum is the gas and unburned powder in the ejecta and since some of the bullet’s speed is lost to air resistance between gun and body, the momentum transferred is necessarily less than the recoil momentum transferred to the shooter and we know that does about as much damage as throwing a medicine ball. The wounding effect is caused by the transmission of energy which purees cells in front of it and throws tissue out to the side of it. Momentum is conserved as it does this because what is thrown to one side is equal and opposite to what is thrown to the other. Heavy bullets are usually slower bullets and so the rate of energy loss that is proportional to the square of velocity is lower. If we take a simple example again we can consider two bullets of the same frontal area and the same energy but with one twice the weight of the other. In this case the half weight bullet must be traveling at √2 or approximately 1.4 times the speed of the heavy bullet. Since its weight is half that of the heavy bullet its momentum will be 0.7 times that of the heavy bullet. Immediately upon impact the lighter bullet will be giving up energy at twice the rate of the heavier bullet. This energy causes tissue destruction mainly to the side of track. That difference will fall until both reach the same velocity. As the lighter bullet is half the weigh of the heavier bullet it will then have half as much remaining energy as the heavier bullet but since it has been traveling faster to that point it will, by then, have penetrated further. Now, with twice as much energy, but the same speed the heavier bullet looses the same amount of energy over the next small increment of penetration but that is only half as much of its total energy. It catches up with and then overtakes the lighter bullet. The heavier bullet does indeed penetrate further but it is not its momentum that makes the difference but the lower rate at which it dissipates its energy. Until it comes to a stop, the heavy bullet is traveling more slowly for most of its track. As a result it does less damage to the side of its track and so has more energy available for penetration. Once the past the point of equal speed the heavier bullet will be doing more damage to the side of track The light bullet gives up energy at its maximum rate at the surface. So does the heavy bullet but, because it is slower, that rate is less. This is an unfortunate fact of physics because we do not want surface level damage but deep level damage. But streamlining and frontal area also play a large part in the rate of energy loss. If we make our bullet streamlined but able to expand relatively slowly we can reduce the initial energy loss and then increase it as the bullet expands to an unstreamlined shape. Typically, if we go from .40 to .90 of an inch we increase the frontal area, and the rate of energy loss, by a factor of 5. Streamlining can increase that factor to somewhere between 7 and about 15 by reducing the initial drag to s low as 0.3 or so. A tough enough bullet and good design can delay full opening for some small but useful distance and reduce the energy wasted close to the surface. Bullet design is more important to fast bullets than slow bullets because fast bullets waste more energy at the surface. This is not that penetration is the most important thing or that width of damage zone is the most important thing. What is important is having the right balance between the two for the expected target. What is best against a man will use its energy at too shallow a level against a grizzly. What is best against a grizzly will go straight through a man and might release only a quarter of its energy – so you might as well use a .380 instead of a 10mm grizzly load on a man unless you can arrange to shoot him end to end. Too much penetration is as bad as too little because it is energy delivered that does the damage. English
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#229
10-01-2009, 10:51 AM
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Why do so many people who haven't BTDT feel that caliber plays a role in the "equation"?
 Shot placement is the be-all end-all. Everything else is trivial....and tiring
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#230
10-01-2009, 10:54 AM
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Not nearly as scientific as English but I wonder if much of the continual (100yrs +) anecdotal reputation of big, slow bullets for stopping power is due to the initial smack of the rounds
Don't laugh yet. I'm thinking that getting hit in the sternum with a ball peen hammer might be a more instant, though less lethal, attention getter that getting run thru with a rapier. Big, heavy and slow if it hits a solid structure might cause a momentary "reset" or even a conscious "that's hurts, time to give up" more than light and fast. I remember stuff that Chic Gaylord wrote in the 1950's or 1960's advocating 200gr .38 SPC over 158gr. Sounds like the only difference would be the momentum. Soft tissue only maybe is more of a wash - thus Gabe and Yoni's experience that pistol hits with calibers between 9mmP and .45 acp don't show much difference. Thoughts?
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